Pause guidance sounds

When you stop in the middle of a journey and are no longer aligned with the direction you want to follow, the app beeps constantly without stopping.

We could pause these beeps, without stopping the journey, and restart them (automatically or manually) when we get going again.

We could have a button on the screen, but the best would be to be able to use a click of the "pause" button on our headphones, which normally controls the music.